[FFmpeg-devel] [PATCH v6] avformat/demux: Add duration_probesize AVOption

[Stefano Sabatini]

On date Friday 2024-03-29 10:26:19 +0100, Nicolas Gaullier wrote:
> Yet another probesize used to get the durations when
> estimate_timings_from_pts is required. It is aimed at users interested
> in better durations probing for itself, or because using
> avformat_find_stream_info indirectly and requiring exact values: for
> concatdec for example, especially if streamcopying above it.
> The current code is a performance trade-off that can fail to get video
> stream durations in a scenario with high bitrates and buffering for
> files ending cleanly (as opposed to live captures): the physical gap
> between the last video packet and the last audio packet is very high in
> such a case.
> 
> Default behaviour is unchanged: 250k up to 250k << 6 (step by step).
> Setting this new option has two effects:
> - override the maximum probesize (currently 250k << 6)
> - reduce the number of steps to 1 instead of 6, this is to avoid
> detecting the audio "too early" and failing to reach a video packet.
> Even if a single audio stream duration is found but not the other
> audio/video stream durations, there will be a retry, so at the end the
> full user-overriden probesize will be used as expected by the user.
> 
> Signed-off-by: Nicolas Gaullier <nicolas.gaullier at cji.paris>
> ---
>  doc/APIchanges              |  3 +++
>  doc/formats.texi            | 19 ++++++++++++++++++-
>  libavformat/avformat.h      | 16 ++++++++++++++--
>  libavformat/demux.c         | 13 ++++++++-----
>  libavformat/options_table.h |  1 +
>  libavformat/version.h       |  2 +-
>  6 files changed, 45 insertions(+), 9 deletions(-)

Looks good to me, will apply in a few days if there are no further
comments.

Thanks.